ST9604-SP 9807211341 West Mockingbird Lane · Dallas, Texas 75247 · 972.647.6700 · www.txi.com
July 21, 1998
Rebcon, Inc.
1868 W. Northwest Highway
Dallas, TX 75220
Attn: Mr. Robert Bibby
RE: Fairway Drive & Beltline Road
Coppell, Texas
8272 8275
The attached concrete mix designs utilizing the appropriate ASTM
C-33 or ASTM C-330 aggregate are proposed for use on the above
referenced project for ready-mixed concrete to be furnished by
TXI.
To ensure that the correct mix is delivered to your project,
please order by the mix design number which appears in the upper
left hand corner of the mix design.
Texas Industries certifies that the above mix designs, when
ordered by specified design identity, and delivered by TXI, will
meet or exceed the indicated design strength at the designated
age when tested in accordance with the applicable and current
ASTM Standards C 31, C 39, C 78, C 172, C 293, applicable
provisions of C 94, and evaluated in accordance with applicable
provisions of ACI Building Code.
TXI would like to be included on your mailing list to receive all
test reports. ASTM C 94 entitles a manufacturer to receive
copies of all test reports when strength of concrete is used as a
basis for acceptance.
Please contact us if you have any questions or require any
additional information. Please notify TXI of approval of the
proposed mix designs prior to their use. Failure to notify us
prior to first placement shall constitute acceptance. To ensure
that the proper mix designs are ordered, please send a copy of
this letter, after approval, to the above referenced project to
be used by the person ordering the concrete for this job.
Sincerely,
Texas Industries
Michael A. Caldarone, P.E.
Manager - Q.A. / Q.C.
Mix #:
Description:
Strength:
8272
5.00SK ADMIX/AEA
3000 psi @ 28 Days
i"CS
MISCELLANEOUS CONCRETE
Maximum Coarse Aggregate:
Maximum Water/Cement Ratio:
Cement/Cementitious Content:
Maximum Placement Slump:
Air Entraining Agent:
Admixture:
1" - #4 CRUSHED STONE
6.20 gal/sack or 0.549 lbs/lb
5.00 sacks (per cubic yard)
4.00 inches
ASTM C-260
ASTM C-494 Type A or D
MATERIAL QUANTITIES PER 1.0 CUBIC YARD AT S.S.D
470 lbs. ASTM C 150 TYPE I CEMENT
1840 lbs. 1" - #4 CRUSHED STONE
1329 lbs. CONCRETE SAND
258 lbs. or 31.0 Gallons of Water
2.0 to 4.0 oz/cwt of ASTM C-494 Type D
Specified Air Content: 4.0% - 6.0%
Placement Slump: 3.00 + or - 1.00 inches
Mix #:
Description:
Strength:
8275
6.50SK ADMIX/AEA
650 psi @ 7 Days
i"CS
PAVING (ASTM C-293)
Maximum Coarse Aggregate:
Maximum Water/Cement Ratio:
Cement/Cementitious Content:
Maximum Placement Slump:
Air Entraining Agent:
Admixture:
1" - #4 CRUSHED STONE
4.77 gal/sack or 0.422 lbs/lb
6.50 sacks (per cubic yard)
4.00 inches
ASTM C-260
ASTM C-494 Type A or D
MATERIAL QUANTITIES PER 1.0 CUBIC YARD AT S.S.D
611 lbs. ASTM C 150 TYPE I CEMENT
1840 lbs. 1" - #4 CRUSHED STONE
1211 lbs. CONCRETE SAND
258 lbs. or 31.0 Gallons of Water
2.0 to 4.0 oz/cwt of ASTM C-494 Type D
Specified Air Content: 4.0% - 6.0%
Placement Slump: 3.00 + or - 1.00 inches
PUMPING NOTES / RECOMMENDATIONS
2.
3.
4.
5 o
6 o
5" minimum diameter lines with no reduction to smaller
lines.
Keep rubber hose to absolute minimum length and plan pipe
with as few 90 degree angles as possible.
Samples for slump and strength tests should be taken @
discharge end of hose for strength guarantee to be valid.
To prime pump lines, a minimum of 8.0 sack grout should be
used for lubrication. In the case of strength concrete,
equivalent strength grout should be used if the grout
remains in the placement.
Pump mixes are based on minimum cement content pumped at
ground level. As pump line increases in length or height
and/or layout configuration changes, additional cement may
be required to assure strength and pumpability at additional
cost to the contractor.
TXI cannot control, and is therefore not responsible for
excessive loss of entrained air content when loss occurs as
a result of boom configuration or free fall discharge from
hose. To ensure minimum air loss when pumping, maintain a
continuous flow of concrete through the entire length of
pipe and do not subject concrete to free fall.
We are enclosing all available back up data for the referenced
mix design(s). If the strength information is not available, or
is insufficient, confirmation tests may have to be conducted by
your laboratory.
Cement, aggregate, and admixture certification have already been
submitted.
Unless otherwise indicated, when the concrete temperature at
point of placement exceeds 90 degrees, TXI will guarantee the
strength performance of the mix design(s) herein submitted up to
a maximum placement temperature of 100 degrees using an ASTM C
494 Type D retarding water-reducer as long as the concrete is
placed within 75 minutes from batch time.
Test Plant (Fahrenheit) Placement Percent ......... 28 Day ........ Cumulative Moving
Number Date Number Ambient Concrete Slump (in) of Air PSI 1 PSI 2 PSI Ay9 Average Av~ of 3 Range
1 04/08/98 12 69 80 5.50 4.4% 3830 3660 3745 3745 170
2 04/08/98 12 62 70 5.50 4.3% 4580 4440 4510 4128 140
3 04/13/98 43 75 78 4.50 N/A 3490 3520 3505 3920 3920 30
4 04/13/98 39 67 70 5.50 N/A 4120 4370 4245 4001 4087 250
5 04/13/98 39 66 68 5.75 N/A 3930 3870 3900 3981 3883 60
6 04/13/98 39 62 68 5.25 N/A 3900 3820 3860 3961 4002 80
7 04/13/98 31 68 78 5.00 4.2% 4180 3910 4045 3973 3935 270
8 04/13/98 31 68 75 4.50 3.6% 4350 4210 4280 4011 4062 140
9 04/14/98 70 79 4.00 4.5% 4090 3980 4035 4014 4120 110
10 04/14/98 67 75 5.00 4.2% 3550 3570 3560 3969 3958 20
11 04/14/98 42 72 79 4.50 N/A 4680 4210 4445 4012 4013 470
12 04/14/98 12 66 78 5.50 4.4% 3840 3920 3880 4001 3962 80
13 04/14/98 12 65 73 5.75 4.2% 4090 4110 4100 4008 4142 20
14 04/15/98 42 75 79 4.50 N/A 4550 4360 4455 4040 4145 190
15 04/16/98 61 70 4.75 4.4% 3560 3580 3570 4009 4042 20
16 04/16/98 58 63 5.00 4.6% 3920 4010 3965 4006 3997 90
17 04/16/98 54 60 5.00 4.4% 3490 3510 3500 3976 3678 20
18 04/16/98 43 70 72 5.00 N/A 3750 3620 3685 3960 3717 130
19 04/17/98 49 60 5.25 4.3% 3690 3740 3715 3947 3633 50
20 04/17/98 42 68 71 4.50 N/A 4660 4420 4540 3977 3980 240
21 04/21/98 52 68 5.25 4.2% 4140 3990 4065 3981 4107 150
22 04/22/98 31 53 67 5.50 N/A 4690 4720 4705 4014 4437 30
23 04/23/98 43 73 78 5.00 N/A 3500 3560 3530 3993 4100 60
24 04/27/98 43 68 73 4.50 N/A 4470 4640 4555 4016 4263 170
25 04/27/98 43 70 78 5.00 N/A 5120 4860 4990 4055 4358 260
26 04/30/98 41 49 58 5.50 N/A 3000 3000 3000 4015 4182 0
27 05/01/98 42 N/A 4540 4840 4690 4040 4227 300
28 05/05/98 38 84 76 5.00 N/A 3910 3880 3895 4035 3862 30
29 05/05/98 38 83 78 5.00 N/A 4250 4360 4305 4044 4297 110
30 05/19/98 76 84 4.50 4.4% 4150 4130 4140 4047 4113 20
66 73 5.02 4.3%
COMMENTARY OF STATISTICAL EVALUATION OF CONCRETE DESIGN RESULTS
Mix Num: 8272
Strength: 3000 psi ~ 28 Days
Paragraph 5.5 of ACI 318-89 provides that as data becomes
available during construction, the amount by which (F'cr) must
exceed the specified value of (F'c) may be reduced, provided:
(a)
30 or more test results are available and average of
test results exceeds that required by Section 5.3.2.1,
using a standard deviation calculated in accordance
with Section 5.3.1.1, or
(b)
15 to 29 test results are available and average of test
results exceeds that required by Section 5.3.2.1, using
a standard deviation calculated in accordance with
Section 5.3.1.2.
The required average compressive strength has been calculated
using a standard deviation calculated in accordance with
ACI 318-89 Section 5.3.1.1 or Section 5.3.1.2 and is the larger
value of these calculations:
F'cr = F'c + 1.34(SD)
= 3000 + 1.34( 447.8)
= 3600
F'cr = F'c + 2.33(SD) - 500
= 3000 + 2.33( 447.8) - 500
= 3543
SUMMARY OF STATISTICAL ANALYSIS
28 Day Test Data
Number of Tests .......................... 30
Maximum Value ............................ 4990 psi
Minimum Value ............................ 3000 psi
Range .................................... 1990 psi
Average Strength ......................... 4047 psi
Standard Deviation ....................... 448 psi
Required Average Strength to satisfy
minimum probability conditions of
ACI 318-89 Section 5.3.2.1 ............... 3600 psi
Design excess beyond code requirements... 447 psi